Wall anchor for electrical conduits

ABSTRACT

A wall anchor for securing electrical conduits or the like to concrete walls, and consisting of a tubular, internally tapered, elastically expansible plug adapted to be inserted freely into a cylindrical socket drilled therefor in the wall, and a correspondingly tapered core member adapted to be driven into the plug whereby to expand the latter into tight frictional engagement with the wall of the socket, and a hook member carried by the core at the outer end of said core and operable, as the core is driven, to clamp an electrical conduit against the wall surface.

United States Patent 1191 Richards Dec. 18, 1973 41 WALL ANCHOR FORELECTRiCAL CONDUITS [76] Inventor: Albert A. Richards, 7127 LafayetteSt., Wyandotte, Kans. 66109 [22] Filed: Aug. 5, 1971 [21] App]. No.:169,278

[52] US. Cl 248/71, 85/84, 248/2205 [511' Int. Cl. F16b 15/04 [58] Fieldof Search 248/71, 223', 220.5;

[56] 7 References Cited UNITED STATES PATENTS 3,022,701 2/1962 Potruch85/83 3.613.497 10/1971 Heldermann 85 84 2,570,957 10/1951 Lee 248/74 R2.326.855 8/1943 1181mm 85/84 3.298.725 1/1967 Boteler 85/84 x FOREIGNPATENTS OR APPLICATIONS 124.974 4/1928 Switzerland 5/82 3/1954Switzerland 85/83 447,768 0/1969 Japan 85/72 231,935 l/l96l Australia85/84 1,167,187 11/1958 France 248/223 7 Primary Examiner--Ramon S.Britts AssistantExaminer -Rodney H. Bonck Att0rney.lohi1 A. HamiltonABSTRACT -.A wall anchor for securing electrical conduits or the like toconcrete walls, and consisting of a tubular, in-

ternally tapered, elastically expansible plug adapted to be insertedfreely into a cylindrical socket drilled therefor in the wall, and acorrespondingly tapered core member adapted to be driven into the plugwhereby toexpandthe latter into tight frictional engagement with thewallof the socket, and a hook member carried by the core at the outer end ofsaid coreand operable, as the core is driven, to clamp an electricalconduit against the wall surface.

1 Claim, 4 Drawing Figures WALL ANCHOR FOR ELECTRICAL CONDUITS' Thisinvention relates to new' and useful improvements in wall anchors, andhas particular reference to a wall anchor for use in stringingelectrical conduits, cables, and the like in dwellings or otherbuildings, being operable to secure said conduits, cables, or the likesecurely to a wall of concrete or other material.

A principal object of the present invention is the proloosely into asocket drilled therefor ina wall, and in-" cluding a hook member adaptedto secure an electrical conduit against said wall, and means wherebysaid anchor assembly may be secured tightly in said socket, and saidhook operated to clamp saidconduit against said wall, by means of asingle operation such as a hammer blow. I g

Other objects are extreme simplicity and economy of construction, andefficiency and dependability of operation. i

With theseobjects in view as well as otherobjects which will appear inthe course of thespecification, reference will be had to theaccompanying drawing, wherein: I i i FIG; 1 is a longitudinal sectionalview, with parts left could be roughened if necessary or desired, aswill appear. I

Core memberis solid, is tapered correspondingly to the taper of bore 16,and is provided with peripheral ribs 30 along a major portion of itslength, said ribs corresponding in contour to ribs 18 of plug 8. Thelength of its tapered portion is slightly less than the length of plug8. The smaller end portion of the core is not ribbed for a distance fromits extreme end, whereby to form a smooth, frusti'o-conical nosepiec'e32. The diameter of the outeror larger end'of the conical portion of thecore is somewhat greater than the normal diameter of the outer or largerend of the bore 14 of the plug.

. The plug is provided at its outer end with a cylindrical extension 34of reduced diameter, and hook 12 extends laterally from the outer end ofsaid extension. Said Q ,hook, which may be integral with or firmlyaffixed to i the plug, is of generally semi-cylindrical curvature, 1

than the normaldiameter of plug 8 is first drilled in wall in elevationand partially broken away, of a wall anchor embodying the presentinvention ,,with the parts shown in a position preparatory to the finalsecuring of the anchor,

FIG. 2 is a view similar to'FlG. 1, but showing the anchor fullysecured, I 1 1 FIG. 3 is a fragmentary face view of the wall and an choras shown in FIG; 2, and

FIG. 4 is a sectional view taken FlG. l.

Like reference numerals apply to similar parts throughout the severalviews, and the numeral 2 applies to a concrete wall,.with the numeral 4designating the surface of said wallto which it is desired to mount anelectrical conduit 6 or the like; It will be apparent, however, that theanchor contemplated by the present invention is applicable also to wallsother than concrete, such as stone, plaster, or the-like.

The wall anchor as shown and: described includes a plug member 8, a coremember 10, and ahook member 12,- all formed of plastic, metal or othersuitable material (plastic illustrated). Plug member 8 isexternallycylindrical, and is tubular, having a circular bore 14 extending thefull length thereof. Throughout'the major portion of the length of saidbore, it is taperingly'enlarged toward one end thereof, as indicated at16,.and the resulting hollow conical surface hasa continuous on linelV-IV of series of peripheral ribs 18 formed thereon, the surfacesdefining each of said ribs being respectively planar and disposed atright angles to the plug axis,and of frustro-conical form with theirlarger diameter ends toward the outer end 20 of the plug. The remainingportion of bore 14 is taperingly enlarged toward the opposite or innerend 22 of the plug, as indicated at 24. Also, the walls of the plug areslotted longitudinally at angularly spaced intervals thereabout asindicated at 26, said slots opening through the outer end of the plugbut terminating short of its inner end 22, extending the full length ofthe ribbed portion 16 of bore 14, and

2 from surface 4 thereof, said socket having a depth generally equal tothe axial length of plug 8, Plug 8 is ,then inserted loosely into thesocket, so that its outer end is generally flush with wall surface 4,and with the larger ,end of bore 14 thereof disposed at itsexposedouter-end. The smaller end of core-10 (nosepiece 32 thereof) isthen inserted into bore 14 of the plug, and

electrical conduit 6, or any other element to be anchored to the wall,is disposed between hook I2 and wall surface 4. The parts then have therelative positionsshown in FIG. 1. Then a strong inward pressure isexerted on the outer end of the core," as by a sharp hammer blowdelivered to the outer end of core extension 34, to drive the coreinwardly in plug bore 14 to the position shown in FIG. 2, or as farasmay ,be per- I "mitted, This clamps conduit 6 firmly in position,be

leaving an uninterrupted ring portion 28 of the plug aligned withportion 24 of the bore. The exterior surface of the plug is smoothlycylindrical as shown, but

tween hook 12 and wall surface 4, the resilience of the hook permittingit to yield and be deformed, whereby to hold theconduit firmly despiteany normal variation in the depth to which the coremay be driven intothe plug. 1

The driving of the core into the plug of course expands the plugresiliently to force its exterior surface into firm engagement with thewall of socket 36 as shown in FIG. 2,.whereby to prevent accidentalwithdrawal of the plug from said socket. As long as the plug is made ofa relatively soft, indentable material such as plastic, it will be seenthat the inherent roughness of the wall of a socket 36 drilled inconcrete, stone or any other material in connection with which theanchor is likely to be used will cause indentation of the plug fullyadequate to secure the plug in the socket Of course, if

"a hard metal plgg is utilized, which ctfld not be readily indented,then'it might be necessary to roughen the exterior surface of the plug,for example by providing ribs thereon similar to internal ribs 18. Thisis considered to be within the scope of the invention. The expansion ofthe plug is of course permitted by slots 26 formed in the wall thereof,the reverse slope of inner portion 24 of the plug bore providing thatring portion 28 of the plug will not be subjected to expansive forces.This ring portion is of course not expandable to any great degree, andexertion thereon of expansive forces by the core would so resist theinward movement of the core as to inhibit the expansion of the slottedportion of the plug.

In some applications, it would be practical to use a plug formedentirely of a softer, more elastic material such as a softer plastic oreven a firm rubber, so that slots 26 could be dispensed with. However,this would so reduce the structural strength of the anchor as tosubstantially reduce its holding power, and the use of a firmer plugmaterial, slotted as shown, is therefore considered preferable.

The interengaging action of plug ribs 18 and core ribs '30 anchors thecore against accidental removal from the plug. Their contour as shownprovides a positive locking action against removal, while at the sametime they may be sufficiently yieldable to deform and pass each other asthe core is driven into the plug. However, the specific contour of theribs, or even the use of ribs at all, is exemplary only and not intendedas a limitation on the scope of the invention. Variousotherconfigurations could be used to provide roughness fully adequatefor the statedpurpose. In fact, if the taper of plug bore 14, and ofcore 10, could be made sufficiently gradual to be self-locking, then notoughening of the cooperating surfaces, would be required at all.However, this would require either that the plug and core beinconveniently long to provide the necessary degree of plug expansion,or that the plug fit very closely in socket 36 and that the socket beformed very accurately, to provide the necessary plug expansion in ashort movement of the core. For these reasons, a steeper taper, withsome type of surface roughening, is preferred.

While I have shown and described a specific embodiment of my invention,it will be readily apparent that many minor changes of structureandoperation could be made without departing from the spirit of theinvention.

What I claim as new and desire to protect by Letters Patent is:

l. A wall anchor comprising:

a. an externally cylindrical, resiliently expansible plug adapted to beinserted loosely into a cylindrical socket formed therefor in a wallfrom an exposed surface of said wall, said plug being tubular and havinga bore taperingly enlarged along a major portion of its length towardthe end thereof exposed at the open end of said socket, and taperinglyenlarged toward the opposite end of said plug member along the remainderof its length, and having longitudinal slots formed therein at angularintervals thereabout, said slots extending the full length of the firstof said tapered bore sections, and into but not through the second ofsaid tapered bore sections,

. a core member tapered correspondingly to the first of said taperedbore sections, and adapted to be inserted smaller end first into saidfirst tapered bore section, and to be driven-therein to expand said pluginto tight engagement with the wall of said socket, and

. a hook member carried by said core member at the larger end thereofandextending laterally therefrom, whereby an object may be securedbetween said hook member and said wall surface as said core member isdriven into said plug member.

1. A wall anchor comprising: a. an externally cylindrical, resilientlyexpansible plug adapted to be inserted loosely into a cylindrical socketformed therefor in a wall from an exposed surface of said wall, saidplug being tubular and having a bore taperingly enlarged along a majorportion of its length toward the end thereof exposed at the open end ofsaid socket, and taperingly enlarged toward the opposite end of saidplug member along the remainder of its length, and having longitudinalslots formed therein at angular intervals thereabout, said slotsextending the full length of the first of said tapered bore sections,and into but not through the second of said tapered bore sections, b. acore member tapered correspondingly to the first of said tapered boresections, and adapted to be inserted smaller end first into said firsttapered bore section, and to be driven therein to expand said plug intotight engagement with the wall of said socket, and c. a hook membercarried by said core member at the larger end thereof and extendinglaterally therefrom, whereby an object may be secured between said hookmember and said wall surface as said core member is driven into saidplug member.